Method of and machine for forming seams in can bodies



April 21,,1931- J.,M. HOTHERSALL 1,801,504

METHOD OF AND MACHINE FOR FORMING SEAMS IN GAN BODIES Filed March 8, 1924 3 Sheets-Sheet l y/Qp 52.2w

,EN, R.

r M, W ATTORNEY Ap 1931- J. M.'HOTHERSALL METHOD OF AND MACHINE FOR FORMING SEAMS IN CAN BODIES Filed March 8, 1924 3. Sheets-Sheet 2 Ap 21, 1931- J. M. HOTHERSALL v 1,301,504

METHOD AND MACHINE FOR FORMING SEAMS IN SAN BODIES Filed March 8, 1924 3 Sheets-Sheet 3 ATTORNEY Patented Apr. 21, 1931 UNITED STATES PATENT OFFICE JOHN M. HOTHERSALL, OF BROOKLYN, NEW YORK, ASSIGNOR- TO AMERICAN CAN COM- PANY, OF NEW YORK, N. Y., A CORPQBATION OF NEW JERSEY METHOD OF AND MACHINE FOR FORMING SEAMS IN CAN BODIES Application filed March 8, 1924. Serial No. 697,718.

The invention relates to a method of and machines for forming metallic containers, and relates more particularly to machlnes for forming the bodies of sheet metal vessels, such as can bodies, and in which the side edges of the formed bodies are secured in a hooked side seam.

The principal object of the invention resides in the production of a sheet metal container body of the character described, the side seam of which is efiiciently and positively hermetically sealed without the use of solder and without employing any welding process. a

In present methods and machines of this general character, where the side edges of the sheet metal body are first provided with hooked flanges and thereafter interlocked to form the scam, the seam so formed is not hermetically tight and, therefore, is unsuitable for the packaging of food products. When it is desired to employ the cans for food products, it is necessary to apply to the side seam of the body a subsequent operation to render the same hermetically ti ht, and this operation is generally effected y the use of solder, which is applied to the interlocked flanges of the side seam. Efforts have also been made to secure the side seam in an hermetic manner by a welding process, but, due to the fact that a very thin sheet of metal 1s present in the usual can body, this latter method has proved unsatisfactory. This is because, in order to form the proper welded joint, it is necessary to employ a high temperature which results in dlscoloration of the container, and this generally renders the completed container unsightly and unfit for preserving food products.

The present invention contemplates the formation of an hermetic seal between the interlocked edges of the seam of a sheet metal container by means of melting, or fusing the relatively thin coating of tin which covers the steel base of the usual well-known and universally used tin plate sheet. This result is attained by means of an electrical current which is applied in a manner sufiicient to raise the temperature of the tin coating to the fusing point, but of a temperature insuflicient to effect or discolor the base of the metallic sheet in the manner described in connection with usual welding processes. g

It is known that attempts have been made to form an hermetic seal by fusing the coating of tin on the metal sheet, but these attempts have generally proved unsuccessful, due to the fact that the bond obtained by the fusing of the coating is of insufficient strength to hold the parts of the container.

together in a permanent metallic seam.

The present invention contemplates the employment of the usual interlocked edges of the container seam to obtain the full necessary strength desired in the seam and thereafter fusing the coating of the metal along the seam so formed merely as a means for completely hermetically sealin the contacting surfaces of the sheet, an without depending upon the fusing operation for any added strength to the seam. In the hooked type of seam generally employed, there are four contacting layers of metal, and three contacting surfaces having a tin coating. By passing an electric current through the four thicknesses of metal, the tin coating on three lines of contact described is caused to completely melt, or fuse, thereby uniting the four adjacent layers of metal in a sin le, hermetically sealed unit; and the hoo ked engagement of the seam so formed prevents this fused union of theparts from being disrupted, due to stresses which would tend to fracture such a union were the same intended to further serve as a binding medium between the contacting edges.

It is a further object of the present invention to provide a machine of the character described wherein the forming of the container is accomplished entirely by automatic mechanisms and the subsequent closing and forming of the fused hermetic seal is also efl'ected automatically.

A still further object of the invention is the provision of an electrical fusing means which is efiicient and rapid in operation, thereby permitting the continuous passage, in rapid succession, of metallic containers to be formed and sealed without any discoloration of the containers and without cessation in their progress through the machine.

The operations of forming the side flanges of the container with hooked ends, engaging the same and bumping or compressing the completed seam, are fully disclosed in' the Patent 1,625,091, ranted April 19, 1927, on the invention of J o n F. Peters, and while the said operations are essential in carrying out the present invention, these mechanisms will not be here described in full details and particulars, and in the drawings disclosing.

a plication, to the particular constructionw ich, for the purpose of explanation, has been made the subject of illustration.

In said drawings,

Figure 1 is a side elevation of a preferred embodiment of the machine constituting the )resent invention, said View being partly broken away and shown partly in vertical section to more clearly illustrate certain of the cooperating elements;

Fig. 2 is an enlarged transverse sectional view on line 2-2 of Fig. 1, and illustrating the seam forming mechanism;

Fig. 3 is a similar view on line 3-3 of Fig. 1, and showing the seam assembling and burn ing mechanism;

Fig. 4 is a similar view on the line 4-4 of Fig. 1, and showing the body rolling, or forming mechanism and sheet blank feeding means;

ig. 5 is a transverse sectional view on line 55 of Fig. 1 and illustrating the seam fusin mechanism ig. 6 is a longitudinal vertical section through a portion of the feeding horn and illustrating the upper fusing roll and its connection to the source of electric power;

Fig. Tis a more enlarged detail sectional view through the seam of a can body as carried between the fusing rollers, and clearly illustrating the various surfaces that are fused together.

Referring to the drawings, 11 is a supporting table, or frame, having supporting egs 12 and which is designed to carry on its upper surface the various mechanisms constituting the invention. As viewed in Fig. 1, the rear, or left-hand portion of the frame is provided with an integral support 13 on which is mounted one end of a body forming horn 14 upon which the can bodies are progressively advanced for the successive forming, seaming and fusing operations. The blank sheets from which the can bodies are formed are conveyed to the rear end of the horn 1-1 by suitable conveyor mechanism sustained at one end by the support 13.

As illustrated, the can body blank conveyer consists preferably of a conveyor chain 15, having upwardly extended lugs 16 which are so spaced and located as to advance the body blanks in the flat to the forming horn 14 at proper predetermined intervals, the said blanks being received by the chain from a suit.. ably disposed stack, or other source (not shown). The upper flight of the eonveyer chain 15 passes over a sprocket wheel 18,

which is, or may be driven from any desired power source and which is mounted upon a shaft 19 journaled in bearings disposed in the support 13 of the frame 11. The bearings .in which the shaft 19 is journaled depend from the under side of the support 13 and are, therefore, not shown in the drawings. The can forming station is illustrated at A in Figs. 1 and 4 and includes the body blank curling rolls 22 and 23, which are located beneath and partially housed within the forming born 14 adjacent the sprocket 18 and are shown mounted upon shafts 2 1 and 25, which are journaled in suitable bearing bracket members 20 and 21. The shafts 24 and 25 have mounted upon their outer ends the mesh ing spur gears, or pinions 26 and 27 whereby the curling rolls 22 and 23 are caused to retate in opposite directions, and one shaft 25 has mounted thereon, adjacent the spur gear 27, a sprocket 28 which is adapted to receive power from any outside source (not shown). The can body blank 17 is advanced by the conveyer chain 15 toward the rolls 22 and 23 and passed therebetween, immediately thereafter striking a deflecting finger, or member 29 which directs the body blank upwardly and in curled form to cause it to pass around and generally conform itself closely to the forming horn 14;. A stop 20 is carried by the horn 14 to intercept the body blank after it has passed around the born 14. The upper surface of the support 13 has positioned thereon, on each side of the upper chain 15, guide members 30 which are designed to properly direct the can body blank 17 to the feeding and forming rollers 22 and 23.

Slidably mounted within and extending longitudinally of the born 14 are reciprocating feeding ars 31 provided with springpressed dogs 32 movably mounted within the bars 31, said dogs being resiliently maintained normally extended beyond the surface of the feeding bars when the latter are reeiprocated in one direction in a manner which is well-known in machines of this general character. The bars 31 are adapted to be reciprocated through any suitable power source (not, shown) to advance the can body blanks along'the horn 14, and the dogs 32 are properly spaced apart so as to positlvely advance the can body blanks a certain predetermined distance along the horn at each reciprocation of the feed bars 31, so that the blanks are brought to rest in proper position for the successive operations to be performed.

After the can body blank has been wrapped or formed about the horn at the curling station, as described, the next reciprocation of the bars 31 advances said blank to what may be termed an idle station, as seen in Fig. 1, and at the forming station, a second blank is ready to be received between the curling rollers. Upon the next succeeding reciprocation of the feed bars 31, the first can body blank is carried to and properly positioned at the side edge flanging or hooking station, generally designated at B in Fig. 1, and illustrated more clearly in Fig. 2. At this station, clamping wings 33 are provided and pivoted at 34 to a bracket 35 carried by the frame 11, said clamping wings being intermittently actuated to clamp the body blank to the born 14. The clamping movement of the wings 33 is obtained through the links 36, which are attached at one end to the wings 33, as at 37, the opposite end of each link being connected or attached to any suitable powersource (not shown). As illus trated in Fig. 2, the blank is clamped to the horn 14 with its side edges extending below the wings 33. These depending edges are folded, or flanged in opposite directions by the rocking, or oscillation of the edging bar 38 which is journaled in bearings 39 and 40 and which is rocked or oscillated from any desired power source applied thereto through the lever connection 41 attached to one end of the bar 38, as at 42. The two depending edges of the body blank are operated upon by means of edging steels 38, embedded in the face of the edging bar 38, each of which steel is provided with two faces, or projections, whichare designed to cooperate with similar projections on the horn 14 and clamping wings 33 to provide hooked side flanges on the body blank. This operation is performed by the steels 38, when the edging bar 38 has oscillated in two directions. When the bar 38 is rocked to the left, as viewed in Fig. 2, the edging steels 38 flange, or bend the depending edges of the body blank to the right, and on subsequent oscillations of the bar 38 and lever 41 in the oppositedireetion, the remaining projections of the adjacent steels contact with the bent side flanges to complete the hooked formation thereof against the cut-out portion of the horn 14 and the lower projecting portion of the righthand clamping wing 33. The hooks so formed are clearly shown in Fig. 3 and are adapted to be engaged with one another at the next station on the horn. As soon as the hooked flanges are formed as described, the clamping wings 33 are released and the can body is advanced along the horn at the next reciprocation of the feed bars 31 to the next ensuing station.

The hooked flange engaging and bumping station is designated at C in Fig. 1 and is more clearly illustrated in Fig. 3. At this station the oppositely formed hooks of the can body blank are engaged by the levers 43 which are pivoted at 44 to the side of an upwardly extended support 45 mounted on the frame 11. The horn '14 is slightly reduced in diameter at this point, in order to allow the opposed hook flanges to be engaged with one another and the body of the blank as, at this point, also engaged alternately at opposite sides by reciprocating clamping members 46, having auxiliary spring-pressed clamping members 46. The clamps 46 and the locking levers 43 are actuated preferably by a common power source (not shown) and the action of the clamps 46 is to alternately engage the sides of the can body blank to securely clamp them to the sides of the horn and permit the levers 43 to lift and superpose one above the other the hooked side flanges of the body blank. The cooperating action of the clamps 46 and levers 43 results in the flanged ends being overlapped and interlocked in hooked engagement with each other. A bumping hammer 47 is disposed directly beneath the horn, below the interlocking hooked flanges of the body blank, and is attached to a slide 48, mounted on the support 45 and which is adapted to be raised and lowered by a crank 49, forming a part of the main shaft 50 and which latter is actuated from any outside power source to raise the hammer 47 at predetermined intervals into contact with the interlocking hooks and with considerable force. This operation results in flattening out the engaged hooked flanges along their entire length and suitably fiattens them into a tightly compressed side seam.

The seamed can body blank is thereafter advanced on the horn 14 in the form of a continuous cylindricai can body, by means of a pair of feeding bars 51 having suitable spring-pressed dogs 51, similar to the dogs 32 contained upon the feed bars 31, and the reciprocating bars 51 are preferably actuated by power received from the feed bars 31 by suitable connections. After the bumping operation to complete the side. scam, the clamping members 46 are retracted and the can body blank advances by the reciprocation of the feed bars 51 to the next station, which is preferably an idle station and best shown in' J the interlocking seam bein D and illustrated in detail in Figs. 5 to 7. The passage of the can body blank through the fusing mechanism results in the tin coating upon the various contacting surfaces of fused, or melted, so as to form an air-tig t hermetic joint after cooling. In order that this fusing of the seam may be accomplished quickly and efficiently, there are illustrated upper and lower cooperating fusing rollers 52 and 53. The roller 52 is rotatably journaled, or mounted within the born 14 by means of a shaft 62, and the lower cooperating roller 53 is similarly mounted upon a shaft 63 journaled in adjustable bearing blocks 64, which are slidably held in uideways 65 of a bracket 60 secured to the rame 11. The roller 53 is adapted to be adjusted with respect to the roller 52 by means of set screws 66, which bear against the blocks 6i and are threaded through a block 68 rigidly attached to the bracket 60 by means of grooves .69 in said bracket. By means of said screws 66. the' lower roller 53 is adjusted with respect to the roller 52 to accommodate the thickness of the seam of the can body to be fused and positive continued engagement of the rollers with the seam of the body blank is effected by the tension of springs 67 bearing upwardly against the bearing blocks 64 in which the lower fusing roller is journaled.

The rollers 52 and 53 are connected to any source of electric power by means of the brushes 54 and 55 and wires 56 and 57. The wire 56 is attached to the inside of the born 14 by means of the screw 58 and is directed through a conduit 59 in the born 14 to the upper roller 52 (Fig. 6). The wire 57 is attached to one leg of the bifurcated bracket 60 by means of the screw 61. The rollers and electrical screw connections described are suitably insulated from the horn and from the bifurcated bracket 60 to permit of continuous and uninterrupted passage of the electrical current between the upper and lower fusing rollers and through the interlocked seam carried therebetween by the rotation of said rollers. The can body to be fused is preferably advanced between said rollers by the reciprocating movement of the feed bars 51.

As a result of the operation above described, the can body seam is subjected to the passage of the electric current during the entire extent of its travel between the fusing rollers, thereby raising the temperature of the tin coating carried by the contacting flange parts to a temperature suflicient to fuse said coating and forming a permanent and complete union of the seam, which is reinforced by the hooked engagement thereof and which results in an hermetic seal, impervious to the passage of air.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention, or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. A machine for making can bodies, comprising means for feeding the metal-coated blanks, a horn upon which the bodies are formed, means for wrapping the blanks about said horn, means for engaging the edges of said blanks to form tubular bodies, means for fusing the metal coating of said engaged edges to form an hermetic seal, and mechanism for holding and operating said parts in timed relation. e

2. A machine for forming sheet metal bodies, comprising means for successively forming the body, interlocking the edges thereof, and fusing the metal coating of said interlocked edges to form an hermetic seal, and mechanism for holding and operating said parts in timed relation.

3. A machine for forming can bodies, comprising means for successively forming the body, seaming the side edges thereof, and fusing the metal coating of said seamed edges to form an hermetic seal, and mechanism for holding and operating said parts in timed relation.

l. A machine for forming can bodies, comprising means for successively shaping the ody of tin coated sheet metal, forming the side edges thereof with hooked side flanges, interlocking said side flanges to form a seam, and fusing the tin coating of the completed seam to hermetically seal the same, and mechanism for holding and operating said parts in timed relation.

5. A machine for forming can bodies, comprising in combination: means for feeding the body blanks, a horn upon which the bodies are shaped, cooperating rollers for wrapping said blanks around said horn, means for forming oppositely turned hooked flanges on the side flanges of said bodies, means for interlocking said hooked side flanges, means for bumping said side flanges to complete a side seam, means for fusing the metal coating of said side seam to form an hermetic seal, and mechanism for holding and operating said parts in timed relation.

6. A machine for making sheet metal bodies, comprising in combination: a forming horn. automatic mechanism for feeding body blanks to horizontal position adjacent said horn, automatic means for wrapping said blanks around said horn in the form of a sheet metal body, automatic means for forming hooked flanges on the side edges of said body blank, automatic 'means for engaging said hooked flanges to form a side seam, automatgage said interlocking hooked flanges, automatic means cooperating with said aforementioned means for fusing the metal coating of the sheet metal body along said side seam to form an hermetic seal, and mechanism for holding and operating said parts in timed relation.

7. A machine. for making can bodies, comprising in combination: a forming horn, rollor mechanism for wrapping sheet metal blanks around said horn, means for oppositely hooking the edges of said blanks,- means for locking said hooked edges in a side seam, means for bumping said seam to compress the same, means for fusing the metalvcoating of said blanks along said side seam to form an hermetic seal, reciprocating means for intermittently advancing said body blanks along said horn from said wrapping means to said fusing means, and mechanism for holding and operating said parts in timed re-- lation.

8. A machine for making can bodies, comprising in combination: a forming horn, means for forming body blanks around said horn, reciprocating means for intermittently advancing said formed blanks along said horn, rocker cams cooperating with said born to form oppositely hooked edges on said blanks, means for engaging said hooked edges in a side seam, means for compressing said edges to form a lock seam, means coopcrating with said horn and with said formed bodies for fusing the metal coating of said can bodies to complete an hermetic seam, and mechanism for holding and operating said parts in timed relation.

9. A machine for making can bodies, comprising in combination: a forming horn, rollor mechanism for wrapping sheet metal blanks around said horn, means for oppositely hooking the edges of said blanks, means for locking said hooked edges in a side seam, means for bumping said seam to compress the same, fusing rollers cooperating with said horn and compressed seam to fuse the metal coating of said seam to hermetically seal the same, and mechanism for holding and operating said parts in timed relation.

10. A machine for making can bodies, comprising in combination: a formin horn, roller mechanism for wrapping s eet metal blanks around said-horn, means for oppositely hooking the edges of said blanks, means for locking said hooked edges in a side seam, means for bumping said seam to compress the same, fusing rollers cooperating with said compressed seam to'fuse the metal coating of said seam to hermetically seal the same, reciprocating means for intermittently advancing sai body blanks along said horn from said wrapping means to said fusing means, and mechanism for holding and operating said parts in timed relation.

11. A process for formin an hermetic seam in sheet metal bodies, w ich consists in forming the body, interlocking the edges thereof, and rolling the seam endwise and heating the same and fusing the metal coating of said interlocked edges to produce an hermetic seal.

12. A process of formin an hermetic seam in sheet metal bodies, whic consists in shaping the body from a sheet metal blank, providing the side edges. thereof with hooked sideflanges, interlocking said side flanges to form a seam, and rolling the seam endwise and heating the same and fusing the tin coating of said interlocked seam to hermetically seal the same.

13. A process of forming an hermetic seam in sheet metal bodies, which consists in shaping the body from a sheet metal blank, providin the side edges thereof with hooked side anges, interlocking the side flanges to form a seam, bumping said seam, and then rolling the seam endwise and heating the same and fusing the tin coating of said bumped seam to hermetically seal the same. 14. The method of making tight the hooked side seam of can bodies, which consists in booking and pressing together the edges of a tinned sheet blank, and then heating and pressing the hooked seam by a rolling pressure along the seam in the direction of its length, the heat being to a degree which fuses the tin and does not fuse the steel.

JOHN M. HOTHERSALL. 

